21 2704RK Ceiling lights have a short to ground.

[Ifixrv]

Ceiling lights have a 0.0 resistance to ground.
Mice usually cause an open.
No issues with mice ever. It is Zone 2 the Green 2 wire.
Anyone have any ideas? Seen this before?

Thanks in advance
Tom

[solv3nt]

Do you mean 0V to ground, or are you measuring resistance?

[Ifixrv]

Measuring Resistance. With the circuit isolated at the panel meter on the green #2 wire (12v side) to the White ground. Dead short. It should measure OL

[solv3nt]

What is your background with electrical?

[flybouy]

Originally Posted by Ifixrv

Measuring Resistance. With the circuit isolated at the panel meter on the green #2 wire (12v side) to the White ground. Dead short. It should measure OL

So if I'm understanding correctly you have removed the positive wire for the lights at the power distribution panel and are reading a dead short to ground. If this is correct then it could be a staple thru the wire somewhere or it could be a defective light fixture, or it could be the wire feeging the slideout lights. If you have lights in the slide-out the wires are run under the trailer and it could be in the connections to that wire. That'sthe first place I'd look.

If the slide-feed is OK then I would remove the light fixtures and disconnect the wires. Remove one light at a time and check the fixture then check the wires feeding it. If the short follows the wire then move to the next fixture and repeat. If you get to the last fixture and the short is still in the power wire then it could be pinched or a mouse could have chewed the insulation and the conductors are touching.

[sourdough]

I've never had mice or squirrels cause an open but I have had them cause shorts. They don't particularly like gnawing through 14/12 ga. wire from what I can tell - but they do like insulation.

Like was mentioned, a staple, crushed wire, loose wire etc. could cause the issue you just have to start isolating.

[Ifixrv]

Thanks for heads up. I didn’t know about the slide lights being in the floor.

[Ifixrv]

CNC field service. Pretty extensive but also used to having a schematic. Keystone says they don’t have schematics.

[chuckster57]

Originally Posted by Ifixrv

CNC field service. Pretty extensive but also used to having a schematic. Keystone says they don’t have schematics.

You have to start at one end or the other…BTDT, Keystone isn’t the only one that doesn’t publish any schematics.

Take each light off and look for metal shavings in the fixture (seen that), if clean then disconnect the positive wire and test. Still shorted, go to the next one. I have spent HOURS chasing a lighting circuit.

At least Keystone has color codes published.


https://www.keystonerv.com/innovatio...r-coded-wiring

[solv3nt]

I'm not sure there's an easy button. Chasing electrical gremlins is always a fun task. I think the only way you'll be able to locate it is the slow and steady approach.